I find that repeating the last/most important three words helps, because it gives the other person the opportunity to talk more, especially if they feel cut off

I find that repeating the last/most important three words helps, because it gives the other person the opportunity to talk more, especially if they feel cut off. This way, you come off as listening but accidentally cut them off for reasons other than you not paying attention or intentionally trying to interrupt — the lag that sometimes happens makes things worse